Wednesday, 26 August 2009

The story so far

After a long pause, here is the fifth instalment of this series on fractals with Octave. This time I will look at a fractal called the Burning Ship because of its output that looks like a ship going up in flames.

Burning Ship

The fractal is a Mandelbrot set that has a generating series defined by:

zn+1=(|Re(zn)|+i|Im(zn)|)2+c

where the Re and Im are the functions that return the real and imaginary parts of a complex number. The initial condition is:

z0=0

This fractal can be directly produced with the mandelbrot function we created in previous articles. In addition, we will take r=200 as a divergence limit.

Octave should open the Gnuplot window and display an image similar to this:

Burning Ship, left centre zoom x30

As usual with a fractal like this, the zoomed image looks very similar to the original. Now let's have a look at a related fractal called the Bird of Prey.

Bird of Prey

In the same way that you can produce interesting variations on the classic Mandelbrot set by changing the power used in the series, we can do the same with the Burning Ship series. So let's increase the power in the series above from 2 to 3: